fs/btrfs/space-info.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 #ifndef BTRFS_SPACE_INFO_H
   4 #define BTRFS_SPACE_INFO_H
   5
   6 #include <trace/events/btrfs.h>
   7 #include "volumes.h"
   8
   9 /*
  10  * Different levels for to flush space when doing space reservations.
  11  *
  12  * The higher the level, the more methods we try to reclaim space.
  13  */
  14 enum btrfs_reserve_flush_enum {
  15         /* If we are in the transaction, we can't flush anything.*/
  16         BTRFS_RESERVE_NO_FLUSH,
  17
  18         /*
  19          * Flush space by:
  20          * - Running delayed inode items
  21          * - Allocating a new chunk
  22          */
  23         BTRFS_RESERVE_FLUSH_LIMIT,
  24
  25         /*
  26          * Flush space by:
  27          * - Running delayed inode items
  28          * - Running delayed refs
  29          * - Running delalloc and waiting for ordered extents
  30          * - Allocating a new chunk
  31          * - Committing transaction
  32          */
  33         BTRFS_RESERVE_FLUSH_EVICT,
  34
  35         /*
  36          * Flush space by above mentioned methods and by:
  37          * - Running delayed iputs
  38          * - Committing transaction
  39          *
  40          * Can be interrupted by a fatal signal.
  41          */
  42         BTRFS_RESERVE_FLUSH_DATA,
  43         BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE,
  44         BTRFS_RESERVE_FLUSH_ALL,
  45
  46         /*
  47          * Pretty much the same as FLUSH_ALL, but can also steal space from
  48          * global rsv.
  49          *
  50          * Can be interrupted by a fatal signal.
  51          */
  52         BTRFS_RESERVE_FLUSH_ALL_STEAL,
  53
  54         /*
  55          * This is for btrfs_use_block_rsv only.  We have exhausted our block
  56          * rsv and our global block rsv.  This can happen for things like
  57          * delalloc where we are overwriting a lot of extents with a single
  58          * extent and didn't reserve enough space.  Alternatively it can happen
  59          * with delalloc where we reserve 1 extents worth for a large extent but
  60          * fragmentation leads to multiple extents being created.  This will
  61          * give us the reservation in the case of
  62          *
  63          * if (num_bytes < (space_info->total_bytes -
  64          *                  btrfs_space_info_used(space_info, false))
  65          *
  66          * Which ignores bytes_may_use.  This is potentially dangerous, but our
  67          * reservation system is generally pessimistic so is able to absorb this
  68          * style of mistake.
  69          */
  70         BTRFS_RESERVE_FLUSH_EMERGENCY,
  71 };
  72
  73 enum btrfs_flush_state {
  74         FLUSH_DELAYED_ITEMS_NR  = 1,
  75         FLUSH_DELAYED_ITEMS     = 2,
  76         FLUSH_DELAYED_REFS_NR   = 3,
  77         FLUSH_DELAYED_REFS      = 4,
  78         FLUSH_DELALLOC          = 5,
  79         FLUSH_DELALLOC_WAIT     = 6,
  80         FLUSH_DELALLOC_FULL     = 7,
  81         ALLOC_CHUNK             = 8,
  82         ALLOC_CHUNK_FORCE       = 9,
  83         RUN_DELAYED_IPUTS       = 10,
  84         COMMIT_TRANS            = 11,
  85 };
  86
  87 struct btrfs_space_info {
  88         spinlock_t lock;
  89
  90         u64 total_bytes;        /* total bytes in the space,
  91                                    this doesn't take mirrors into account */
  92         u64 bytes_used;         /* total bytes used,
  93                                    this doesn't take mirrors into account */
  94         u64 bytes_pinned;       /* total bytes pinned, will be freed when the
  95                                    transaction finishes */
  96         u64 bytes_reserved;     /* total bytes the allocator has reserved for
  97                                    current allocations */
  98         u64 bytes_may_use;      /* number of bytes that may be used for
  99                                    delalloc/allocations */
 100         u64 bytes_readonly;     /* total bytes that are read only */
 101         u64 bytes_zone_unusable;        /* total bytes that are unusable until
 102                                            resetting the device zone */
 103
 104         u64 max_extent_size;    /* This will hold the maximum extent size of
 105                                    the space info if we had an ENOSPC in the
 106                                    allocator. */
 107         /* Chunk size in bytes */
 108         u64 chunk_size;
 109
 110         /*
 111          * Once a block group drops below this threshold (percents) we'll
 112          * schedule it for reclaim.
 113          */
 114         int bg_reclaim_threshold;
 115
 116         int clamp;              /* Used to scale our threshold for preemptive
 117                                    flushing. The value is >> clamp, so turns
 118                                    out to be a 2^clamp divisor. */
 119
 120         unsigned int full:1;    /* indicates that we cannot allocate any more
 121                                    chunks for this space */
 122         unsigned int chunk_alloc:1;     /* set if we are allocating a chunk */
 123
 124         unsigned int flush:1;           /* set if we are trying to make space */
 125
 126         unsigned int force_alloc;       /* set if we need to force a chunk
 127                                            alloc for this space */
 128
 129         u64 disk_used;          /* total bytes used on disk */
 130         u64 disk_total;         /* total bytes on disk, takes mirrors into
 131                                    account */
 132
 133         u64 flags;
 134
 135         struct list_head list;
 136         /* Protected by the spinlock 'lock'. */
 137         struct list_head ro_bgs;
 138         struct list_head priority_tickets;
 139         struct list_head tickets;
 140
 141         /*
 142          * Size of space that needs to be reclaimed in order to satisfy pending
 143          * tickets
 144          */
 145         u64 reclaim_size;
 146
 147         /*
 148          * tickets_id just indicates the next ticket will be handled, so note
 149          * it's not stored per ticket.
 150          */
 151         u64 tickets_id;
 152
 153         struct rw_semaphore groups_sem;
 154         /* for block groups in our same type */
 155         struct list_head block_groups[BTRFS_NR_RAID_TYPES];
 156
 157         struct kobject kobj;
 158         struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
 159 };
 160
 161 struct reserve_ticket {
 162         u64 bytes;
 163         int error;
 164         bool steal;
 165         struct list_head list;
 166         wait_queue_head_t wait;
 167 };
 168
 169 static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
 170 {
 171         return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
 172                 (space_info->flags & BTRFS_BLOCK_GROUP_DATA));
 173 }
 174
 175 /*
 176  *
 177  * Declare a helper function to detect underflow of various space info members
 178  */
 179 #define DECLARE_SPACE_INFO_UPDATE(name, trace_name)                     \
 180 static inline void                                                      \
 181 btrfs_space_info_update_##name(struct btrfs_fs_info *fs_info,           \
 182                                struct btrfs_space_info *sinfo,          \
 183                                s64 bytes)                               \
 184 {                                                                       \
 185         const u64 abs_bytes = (bytes < 0) ? -bytes : bytes;             \
 186         lockdep_assert_held(&sinfo->lock);                              \
 187         trace_update_##name(fs_info, sinfo, sinfo->name, bytes);        \
 188         trace_btrfs_space_reservation(fs_info, trace_name,              \
 189                                       sinfo->flags, abs_bytes,          \
 190                                       bytes > 0);                       \
 191         if (bytes < 0 && sinfo->name < -bytes) {                        \
 192                 WARN_ON(1);                                             \
 193                 sinfo->name = 0;                                        \
 194                 return;                                                 \
 195         }                                                               \
 196         sinfo->name += bytes;                                           \
 197 }
 198
 199 DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info");
 200 DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
 201
 202 int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
 203 void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
 204                                 struct btrfs_block_group *block_group);
 205 void btrfs_update_space_info_chunk_size(struct btrfs_space_info *space_info,
 206                                         u64 chunk_size);
 207 struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
 208                                                u64 flags);
 209 u64 __pure btrfs_space_info_used(struct btrfs_space_info *s_info,
 210                           bool may_use_included);
 211 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
 212 void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
 213                            struct btrfs_space_info *info, u64 bytes,
 214                            int dump_block_groups);
 215 int btrfs_reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
 216                                  struct btrfs_space_info *space_info,
 217                                  u64 orig_bytes,
 218                                  enum btrfs_reserve_flush_enum flush);
 219 void btrfs_try_granting_tickets(struct btrfs_fs_info *fs_info,
 220                                 struct btrfs_space_info *space_info);
 221 int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
 222                          struct btrfs_space_info *space_info, u64 bytes,
 223                          enum btrfs_reserve_flush_enum flush);
 224
 225 static inline void btrfs_space_info_free_bytes_may_use(
 226                                 struct btrfs_fs_info *fs_info,
 227                                 struct btrfs_space_info *space_info,
 228                                 u64 num_bytes)
 229 {
 230         spin_lock(&space_info->lock);
 231         btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
 232         btrfs_try_granting_tickets(fs_info, space_info);
 233         spin_unlock(&space_info->lock);
 234 }
 235 int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes,
 236                              enum btrfs_reserve_flush_enum flush);
 237 void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info);
 238 void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info);
 239 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
 240
 241 #endif /* BTRFS_SPACE_INFO_H */